#include <bits/stdc++.h>
#define int long long
#define mod 1000000007
#define endl '\n'
using namespace std;
signed main(){
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
int n,s;
cin>>n>>s;
int arr[n];
for(int i=0;i<n;i++){
cin>>arr[i];
}
vector<pair<int,int>>vct;
bool bl;
do{
bl=false;
for(int i=0;i<n;i++){
if(i<n-1&&(arr[i]^arr[i+1])<arr[i]){arr[i]^=arr[i+1];vct.push_back({i+1,i+2});bl=true;}
if(i>0&&(((arr[i]^arr[i-1])>arr[i])||((arr[i]^arr[i-1])<arr[i]&&arr[i]>=arr[i+1]))){arr[i]^=arr[i-1];vct.push_back({i+1,i});bl=true;}
}
}while(bl);
cout<<vct.size()<<endl;
for(auto i:vct)cout<<i.first<<' '<<i.second<<endl;
}
//5 1 1 1 6 5
//5 5 6 5 6
